CVE-2026-87853: SSSD's IdP authentication provider · CWE-187
Source GCVE Database
Not known to be exploited · CVSS 7.5 High : patch Red Hat Enterprise Linux 10 soon.
Data as of 11 Nov 2026, 16:47 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.5 |
|---|
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 9 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10sssd | Affected– | Fixed in– |
| Red Hat Enterprise Linux 10sssd | Affected– | Fixed in– |
| Red Hat Enterprise Linux 6sssd | Affected– | Fixed in– |
| Red Hat Enterprise Linux 7sssd | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8sssd | Affected– | Fixed in– |
| Red Hat Enterprise Linux 9sssd | Affected– | Fixed in– |
AI-suggested
Red Hat has released an official security update for SSSD in Red Hat Enterprise Linux 10 to address this vulnerability. Users should apply the update as described in the Red Hat advisory RHSA-2026:77534 and the related article https://access.redhat.com/articles/11258. No additional mitigations are specified by the vendor, and applying the update fully resolves the issue.
Description
A vulnerability in SSSD's IdP authentication provider allows an attacker to impersonate another user if the attacker's IdP identifier is a strict prefix of the target user's identifier. This occurs because the eval_access_token_buf() function uses a prefix comparison instead of an exact match when validating the OIDC subject identifier.
References
- nvd.nist.gov/vuln/detail/CVE-2026-87853 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:77534 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:98559 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-87853 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2530888 (opens in a new tab)